Jacob babab



UNITED STATES PATENT OFFICE.

JACOB BARAB, 0E DOVER, NEW JERSEY, Assrenon 'ro HERCULES roWnEn. COMPANY,

OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE.

No Drawing.

T 0 all whom it may concern:

Be itknown that I, JACOB BARAB, a citizen of the United States, residing at Dover, county of Morris, and State of New Jersey, have invented a new and useful Improvement in Nitroglycols, of which the following is a full, clear, and exact description.

It has been known for years that the glycols, such as ethylene, butylene and propylene, are capable of nitration to produce explosives analogous in their properties to nitroglycerin, and such capacity might be said to be quite obvious in view of the analogous character of glycol and glycerin. Equally obvious, of course, is the possibility of nit-rating any mixture of glycol's. However, until comparatively recently, the possibilities in this direction have been of only academic interest, because of the impossibility of producing glycols on an economical and commercial scale. Efforts have been made to produce these glycols by cracking oil gas, chlorinating the unsaturated derivatives to chlorhydrins, and making the glycols from the chlorhydrins. The chlorination of these unsaturated derivatives to chlorhydrins presented, for some time, apparently insuperable difiiculties. Bringing them in contact with chlorin gas in any known way resulted, so far as any measure of success was attained, in the production of dichlorids, or so-called Dutch liquid, which could not be successfully converted to glycol. \Vithin a comparatively recent period. however, successful processes have been developed for the chlorination to chlorhydrin of certain of the olefins on a commercial scale, and thus, for the first time, the possibilities of nitrating glycols derived from these olefin chlorhydrins began to assume a practical importance.

It has been assumed that the usual processes in general use for the manufacture of nitroglycerin from glycerin could be applied unchanged to the manufacture of nitroglycol from glycol, but my own exhaustive experiments demonstrated that thereby no explosive could be thus produced that would in any sense meet commerclal requlrements. Thus, in the purification of the material after nitration, the washing alternately with ater and sodium carbonate was found not Specification of Letters Patent.

Patented June 1'7, 1919.

Application filed July 24, 1918-. Serial No. 246,453. v

to be practicable and it was discovered that it was essential to avoid the use of sodium carbonate. I eventually succeeded, however, in nitrating propylene glycol, and my preferred process for so doing is set forth in an application filed by me July 1-1, 1917, Serial 1 0. 181,561. This propylene glycol dinitrate possesses certain qualities which, in the literature of the art, have been ascribed to nitrated glycols generally or which might have been taken for granted by a chemist possessing ordinary theoretical knowledge of the'subject, but it exhibited other qualities Without which it would hardly have been available as a substitute for nitroglycerin; and I believe the disclosures of my said application were the first in the art to give such information with respect to the manufacture of a nitroglycol as would enable those skilled in the art to make the explosive without the necessity of independent experimentation. Among the valuablequalities of. propylene glycol dinitrate, aside from its very low freezing point, are its relative insensitiveness to friction and shock as demonstrated by the hammer test, its non-hygroscopicity, its very high boiling point, its stability above the highest range of atmospheric temperature, its gradual evaporation without explosion when subjected to a gradual elevation of temperature to an exceedingly high point, its decomposition without exploding when dropped into a flame, and its endurance of the Abel heat test at 71 C. for a prolonged period.

There are certain objections to propylene glycol dinitrate that by no means offset its advantages or constitute a real hindrance to its practicable use but which, if they could be removed even in degree, would enhance the practical value of the explosive. Thus it is much more volatile at atmospheric temperatures than nitroglycerin. Again, its oxygen balance is comparatively low, there being a deficiency of about 29% as compared with the oxygen required to secure ideal conditions of combustion. This deficiency may readily be supplied by adding an oxygen carrier. Thus, when absorbed in wood desired point. However, it is obvious that it is desirable, if possible, to produce a n1- troglycol Whose-oxygen balance, wlthout the addition of an oxygen carrier, w1ll be relatively high.

N itrated butylene glycol failsto meet the requirements. Its oxygen balance is much lower than that of nitrated propylene glycol and its volatility is very high. Y

I have made exhaustive experiments wlth ethylene glycol and have found that the mtrated product possesses qualities analogous to those of nitrated propylene glycol. Thus, like nitrated propylene glycol, when heated in a capilliary tube, it burns wlthout explosion, it is stable at the highest range of atmospheric temperature, and evaporates withouaexplosion when sub ected to a gradual elevation of temperature to an exceedingly high point. In certain respects, however, it is not comparable in value to nitrated propylene glycol. Thus, the freezing point of nitrated ethylene glycol is about l8 to 19 C. On the other hand, the freezing point of nitrated propylene glycol is so low that I have not been able to deter mine it. Upon cooling, no viscosity was observable until about 48 C. was reached, and even at.77 0., while the mass was quite stiff, it had not solidified. Nitrated ethylene glycol cannot, therefore, be said to be non-freezing at atmospheric temperatures.

- In severely cold weather, it would be necclimate where below zero of the other essary, in its manufacture, to warm it to prevent freezing. Itwould possess no'practical advantage over nitroglycerin in any (Fahrenheit) temperature is prevalent. A I Again, nitrated ethylene glycol cannot compare with nitrated propylene glycol with respect to sensitiveness to shock or'friction.

. It is much less sensitive to shock'or friction, however, than nitroglycerin, although, when sub ected to a severe .h

ammer test, it explodes, like nitroglycerin, whereas propylene glycol dinitrate does not.

. N itrated ethylene glycol, however, has the advantage over nitrated propylene glycol of having no deficiency in oxygen and the secondary advantage of being less volatile.

N itrated butylene glycol possesses no advantages over either ofthe other two ni-' trated products, but its disadvantages are so pronounced that its practical use can hardly be given serious consideration. Thus, even nitrated propylene glycol and nitrated ethylene glycolare volatile as compared with nitroglycerin, but the butylene glycol is much higher than either 0 two nitroglycols and its oxygen defic1ency is far greater than that of nitrated propylene glyco The above experiments, have led to the discovery that an explosive superior to propylene glycol dinitrate can be produced by the still so low it gradually distinctly harmful.

-uct is. encountered volatility of nitrated in various proportions, say'from 40 to 60 7 per cent. of each, or by nitrating a mixture of the two glycols. The explosive possesses the distinct advantage over nitrated propyleneglycol of having a much higher oxygen balance and a somewhat lower volatility. While the freezing point is much higher than that of nitrated propylene glycol, it is as to warrant its designation as a non-freezing explosive. With approximately equal proportions of the two nitrated products, the freezing point would be in the neighborhood of 40 C. I prefer to employ from 4:0 to per cent. nitrated ethylene glycol and from'50 to per cent. nitrated propylene glycol. The proportion of theformer should not be lessvthan 35"per cent. or above 60 per cent, while the proportion of the latter should not be less than 10 per cent. or above 65 per cent.

An unexpected sive is; that it possesses a strength greater than that of either of its constituent explosives.

It is quite practicable to mix the two glycols an nitrate them together. The proquality of the new explocedure may be the same as in thegmanufacnitrate an equal weight of propylene glycol requires only 166 pounds of nitric acid. A-

mlxture of ethylene and propylene glycols also requires substantially less nitric acid than does glycerin. 100 pounds of a mixture of 35 per cent. ethylene glycol and 65 per. cent. propylene glycol require 179 pounds of nitric acid. Instead of washing with water and sodium carbonate solutions, as in the purification of nitroglycerin, the washing should be with water and weak ammonia solutions. Any substantial quantity of sodium carbonate in the washing solution is If the two glycols are nitrated separately, ammonia solution only in the washing of the nitrated propylene glycol, and use only pure water in washing the nitrated ethylene glycol. The specific process set forth in my said application may be advantageously used. N o difliculty in stabilizing the prodif it be thoroughly washed.

A distinctive advantage in nitrating the mixed glycols is that it is more economical to convert amixture ofolefinsto chlorhydrin and then reduce to glycol than to chlorinate propylene and ethylene separately and make a pure glycol from each. these two glycols is therefore a cheaper prod- I prefer to use the weak- The mixture of I uct than either of the pure glycols, so that my new explosive is both cheaper than, and superior to, nitrated propylene glycol.

It is important, however, if the pure chlorhydrins or pure glycols-are not obtained separately and afterward mixed and nitrated, that the mixture of chlorhydrins or mixture of glycols should not contain, in substantial proportions, butylene chlorhy-- drin or butylene glycol; So far as butylene glycol is present in the mixture of glycols to be nitrated, it is an impurity. The-presence ofa negligible percentage of the butylene derivatives (say one or two per cent.) is not a serious matter, but if present in a substantial proportion, it so increases the volatility of the final product, besides seriously impairing its qualities in other respects, that the explosive is not only dis tinctly inferior to nitrated propylene glycol,

but would be commercially unacceptable.

\Vhen absorbed in any of the usual ab sorbents employed in the manufacture of dynamite, the new explosive, like nitrated propylene glycol, retains all its valuable qualities, and is non-exuding under general conditions of use.

Notwithstanding the insensitiveness to friction of the solid explosive, it can be detonated satisfactorily by means of a weak primer.

The new explosive used in admixture with nitroglycerin and the mixture of nitroglycols and nitroglycerinmay-be absorbed in any of the standard absorbtives for nitroglycerin. For example, when added to nitroglycerin, it lowers the latters process freezing point and reduces lts sensitlveness to heat, friction and shock.

Another valuable quality of the liquid explosive is that it forms a colloid when mixed with nitrocellulose and the resultant gelatin explosive has valuable properties distinguishing it from nitroglycerin gelatinsu A satisfactor composition comprises 14 parts of nitroce lulose (showing 12.25 per cent. nitrogen) and 100,.parts of nitrated propylene and ethylene glycol.

The new explosive may also be used in admixture with Intro-compounds, as, for example, trinitrotoluol or trinitrotoluol oils.

Having now fully described my invention, what I claim and desire to protect by Letters Patent is:

1. A nitroglycol explosive composed practically entirely of nitrated propylene and ethylene glycol.

2. An explosive containing a substantial proportion of nitrated glycol derived from oil gas, said nitrated glycol being composed practically entirely of nitrated propylene and ethyleneglycol.

i 3. A nitroglycol explosive containing a substantial proportion of nitrated glycol de rived from oil gas, said nitrated glycol be-,

&. A nitroglycol explosive composed practica-lly entirely of nitrated propylene and nitrated ethylene glycol each in the proportion of between 40 and 60 per cent. of the whole.

5. An explosive comprising a substantial proportion of nitrated glycol derived from oil gas, said nitrated glycol being composed practically entirely" of nitrated propylene andet-hy lene glycol, in which the amount of nitrated propylene glycol exceeds the amount of nitrated ethylene glycol by not more than 33% per cent.

In testimony of which invention, I have hereunto setmy hand, at Kenvil, N. J on this 17 day of July, 1918.

JACOB BARAB. 

